Estimated Transfer of Perfluoroalkyl Substances (PFAS) from Maternal Serum to Breast Milk in Women Highly Exposed from Contaminated Drinking Water: A Study in the Ronneby Mother-Child Cohort

Legacy and alternative per- and polyfluoroalkyl substances spatiotemporal distribution in China: Human exposure, environmental media, and risk assessment

In recent decades, China's rapid development has led to significant environmental pollution from the widespread use of chemical products. Per- and polyfluoroalkyl substances (PFAS) are among the most concerning pollutants due to their persistence and bioaccumulation. This article assesses PFAS exposure levels, distribution, and health risks in Chinese blood, environment, and food. Out of 4037 papers retrieved from November 2022 to December 31, 2023, 351 articles met the criteria. Findings show perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) as the main PFAS in both Chinese populations and the environment. The highest PFOA levels in Chinese populations were in Shandong (53.868 ng/mL), while Hubei had the highest PFOS levels (43.874 ng/mL). Similarly, water samples from Sichuan (2115.204 ng/L) and Jiangsu (368.134 ng/L) had the highest PFOA and PFOS levels, respectively. Although localized areas showed high PFAS concentrations. Additionally, developed areas had higher PFAS contamination. The researches conducted in areas such as Qinghai and Hainan remain limited, underscoring the imperative for further investigation. Temporal analysis indicates declining levels of some PFAS, but emerging alternatives require more research. Limited studies on PFAS concentrations in soil, atmosphere, and food emphasize the need for comprehensive research to mitigate human exposure.

Exploring perfluoroalkyl substances contamination in human breast milk: First ghanaian study

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) represent a category of synthetic organic chemical contaminants that have garnered increasing attention due to their potential adverse impacts. Existing research underscores the contamination of human breast milk by PFAS, raising concerns regarding potential deleterious health effects in children. The study aimed to explore the levels of some PFAS in human breast milk in a previously unstudied population to determine the extent of infants' exposure. The research was conducted at Ho Teaching Hospital in Ghana. The study protocol was reviewed and approval by University of Health and Allied Sciences Ethics Research Committee (UHAS-REC). Twenty-nine (29) mothers, aged 18-44 years, were enrolled in the research. Sample collection spanned from December 28, 2020 to June 30, 2021. Ten millilitres (10 mL) of breast milk were collected from each participant into cleaned bottles from day of birth to after two weeks postpartum, following a standardized protocol and stored at -20 °C. Sample preparation and analysis employed solid phase extraction methodology. Subsequently, the processed extracts were subjected to analysis using ultra-high-performance liquid chromatography (UPLC-MS/MS). The data obtained were analysed using IBM SPSS Statistics version 26, Excel 2016, and Xlstat 2022. Descriptive statistics were employed to summarize the study variables. The mean/mode input method was used to treat missing data. The median and interquartile range (IQR) of PFAS concentrations in the breast milk were: PFHxA, 6.0 ng/L(IQR, 2.2 ng/L), PFHpA, 5.6 ng/L(IQR, 2.1 ng/L), PFOA, 72.0 ng/L(IQR, 16.0 ng/L), and PFOS, 93.0 ng/L(IQR, 8.0 ng/L) ng/L) respectively. PFOS and PFOA were the most dominant PFAS in the breast milk which is consistent with worldwide reports. The levels of PFAS, particularly PFOS and PFOA, in breast milk points to seemingly high levels of PFAS exposure and contamination of mothers and neonates in the region.

Determinants of per- and polyfluoroalkyl substances (PFAS) exposure among Wisconsin residents

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) include thousands of manufactured compounds with growing public health concerns due to their potential for widespread human exposure and adverse health outcomes. While PFAS contamination remains a significant concern, especially from ingestion of contaminated food and water, determinants of the variability in PFAS exposure among regional and statewide populations in the United States remains unclear.

OBJECTIVES

The objective of this study was to leverage The Survey of the Health of Wisconsin (SHOW), the only statewide representative cohort in the US, to assess and characterize the variability of PFAS exposure in a general population.

METHODS

This study sample included a sub-sample of 605 adult participants from the 2014-2016 tri-annual statewide representative sample. Geometric means for PFOS, PFOA, PFNA, PFHxS, PFPeS, PFHpA, and a summed measure of 38 analyzed serum PFAS were presented by demographic, diet, behavioral, and residential characteristics. Multivariate linear regression was used to determine significant predictors of serum PFAS after adjustment.

RESULTS

Overall, higher serum concentrations of long-chain PFAS were observed compared with short-chain PFAS. Older adults, males, and non-Hispanic White individuals had higher serum PFAS compared to younger adults, females, and non-White individuals. Eating caught fish in the past year was associated with elevated levels of several PFAS.

DISCUSSION

This is among the first studies to characterize serum PFAS among a representative statewide sample in Wisconsin. Both short- and long-chain serum PFAS were detectable for six prominent PFAS. Age and consumption of great lakes fish were the most significant predictors of serum PFAS. State-level PFAS biomonitoring is important for identifying high risk populations and informing state public health standards and interventions, especially among those not living near known contamination sites.

Association of diet with per- and polyfluoroalkyl substances in plasma and human milk in the New Hampshire Birth Cohort Study

Per- and polyfluoroalkyl substances (PFAS) are related to various adverse health outcomes, and food is a common source of PFAS exposure. Dietary sources of PFAS have not been adequately explored among U.S. pregnant individuals. We examined associations of dietary factors during pregnancy with PFAS concentrations in maternal plasma and human milk in the New Hampshire Birth Cohort Study. PFAS concentrations, including perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), and perfluorodecanoate (PFDA), were measured in maternal plasma collected at ∼28 gestational weeks and human milk collected at ∼6 postpartum weeks. Sociodemographic, lifestyle and reproductive factors were collected from prenatal questionnaires and diet from food frequency questionnaires at ∼28 gestational weeks. We used adaptive elastic net (AENET) to identify important dietary variables for PFAS concentrations. We used multivariable linear regression to assess associations of dietary variables selected by AENET models with PFAS concentrations. Models were adjusted for sociodemographic, lifestyle, and reproductive factors, as well as gestational week of blood sample collection (plasma PFAS), postpartum week of milk sample collection (milk PFAS), and enrollment year. A higher intake of fish/seafood, eggs, coffee, or white rice during pregnancy was associated with higher plasma or milk PFAS concentrations. For example, every 1 standard deviation (SD) servings/day increase in egg intake during pregnancy was associated with 4.4 % (95 % CI: 0.6, 8.4), 3.3 % (0.1, 6.7), and 10.3 % (5.6, 15.2) higher plasma PFOS, PFOA, and PFDA concentrations respectively. Similarly, every 1 SD servings/day increase in white rice intake during pregnancy was associated with 7.5 % (95 % CI: -0.2, 15.8) and 12.4 % (4.8, 20.5) greater milk PFOS and PFOA concentrations, respectively. Our study suggests that certain dietary factors during pregnancy may contribute to higher PFAS concentrations in maternal plasma and human milk, which could inform interventions to reduce PFAS exposure for both birthing people and offspring.

Serum concentrations of legacy, alternative, and precursor per- and polyfluoroalkyl substances: a descriptive analysis of adult female participants in the MIREC-ENDO study

BACKGROUND

Several legacy and emerging per- and polyfluoroalkyl substances (PFAS) have been regulated around the world. There is growing concern over the proliferation of alternative PFAS, as well as PFAS precursors. Biomonitoring data for PFAS are critical for assessing exposure and human health risk.

METHODS

We collected serum samples from 289 adult female participants in a 2018-2021 follow-up study of the Maternal-Infant Research on Environmental Chemicals (MIREC) Canadian pregnancy cohort. Samples were analyzed for 40 PFAS using ultra-performance liquid chromatography-tandem mass spectrometry. For those compounds with > 50% detection, as well as the sum of these compounds, we describe serum concentrations and patterns of exposure according to sociodemographic and obstetrical history characteristics.

RESULTS

17 out of 40 PFAS were detected in > 50% of samples with 7 of these detected in > 97% of samples. Median [95th percentile] concentrations (µg/L) were highest for PFOS (1.62 [4.56]), PFOA (0.69 [1.52]), PFNA (0.38 [0.81]), and PFHxS (0.33 [0.92]). Geometric mean concentrations of PFOA and PFHxS were approximately 2-fold lower among those with more children (≥ 3 vs. 1), greater number of children breastfed (≥ 3 vs. ≤ 1), longer lifetime duration of breastfeeding (> 4 years vs. ≤ 9 months), and shorter time since last pregnancy (≤ 4 years vs. > 8 years). We observed similar patterns for PFOS, PFHpS, and the sum of 17 PFAS, though the differences between groups were smaller. Concentrations of PFOA were higher among "White" participants, while concentrations of N-MeFOSE, N-EtFOSE, 7:3 FTCA, and 4:2 FTS were slightly higher among participants reporting a race or ethnicity other than "White". Concentrations of legacy, alternative, and precursor PFAS were generally similar across levels of age, education, household income, body mass index, and menopausal status.

CONCLUSIONS

We report the first Canadian biomonitoring data for several alternative and precursor PFAS. Our findings suggest that exposure to PFAS, including several emerging alternatives, may be widespread. Our results are consistent with previous studies showing that pregnancy and breastfeeding are excretion pathways for PFAS.

Effects of developmental exposure to individual and combined PFAS on development and behavioral stress responses in larval zebrafish

Per- and polyfluoroalkyl substances (PFAS) are a class of synthetic chemicals known for their widespread use and persistence in the environment. Laboratory and epidemiological studies investigating these compounds have signaled their neurotoxic and endocrine-disrupting propensities, prompting further research into their effects on behavioral stress responses and their potential role as risk factors for stress-related disorders such as anxiety and depression. This study elucidates the ramifications of early developmental exposures to individual and combined PFAS on the development and behavioral stress responses of larval zebrafish (Danio rerio), an established model in toxicological research. Wild-type zebrafish embryos were enzymatically dechorionated and exposed to PFOS, PFOA, PFHxS, and PFHxA between 6 and 120 h post-fertilization (hpf). We targeted environmentally relevant concentrations stemming from the USEPA 2016 Hazard Advisory Limit (HAL, 0.07 μg/L) and folds higher (0.35, 0.7, 1.75, and 3.5 μg/L). Evaluations at 120 hpf encompassed mortality, overall development, developmental defects, and larval activity both at baseline stress levels and following exposure to acute stressors (acoustic and visual). Larval exposure to PFOA, PFOS, or PFHxS (0.07 μg/L or higher) elicited significant increases in mortality rates, which capped at 23.1%. Exposure to individual chemicals resulted in limited effects on overall development but increased the prevalence of developmental defects in the body axis, swim bladder, pigmentation, and eyes, as well as the prevalence of yolk sac and pericardial edemas. Larval activity at baseline stress levels and following exposure to acute stimuli was significantly altered. Combined exposure to all four chemicals intensified the breadth of developmental and behavioral alterations, suggesting possible additive or synergistic effects. Our findings shed light on the developmental and neurobehavioral disturbances associated with developmental exposure to PFAS at environmentally relevant concentrations, the added risks of combined exposures to these chemicals, and their possible role as environmental risk factors for stress-related disorders.

Involvement of per- and polyfluoroalkyl compounds in tumor development

Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic persistent chemicals, which are used in many industrial and commercial applications. Hundreds of different PFAS have been identified in the environment and they are commonly found also in human blood. Due to the chemical stability and extensive use, PFAS pose a risk for human health and wildlife. Mounting evidence indicates that PFAS-exposure adversely affects many organs including liver, kidney, and reproductive tissues and induces tumors in laboratory rodents. Epidemiological studies show association between PFAS-exposure and some tumors also in humans. Effects of PFAS-exposure are complex and obviously do not depend only on the concentration and the structure of PFAS, but also on age and sex of the exposed individuals. It has been difficult to show a causal link between PFAS-exposure and tumors. Moreover, molecular mechanisms of the PFAS effects in different tissues are poorly understood. PFAS are not directly mutagenic and they do not induce formation of DNA binding metabolites, and thus are assumed to act more through non-genotoxic mechanisms. In this review, we discuss the involvement of PFAS-compounds in tumor development in tissues where PFAS exposure has been associated with cancer in epidemiological and animal studies (liver, kidney, testicle and breast). We will focus on molecular pathways and mechanisms related to tumor formation following PFAS-exposure.

Exploring the impact of prenatal perfluoroalkyl and polyfluoroalkyl substances exposure on blood pressure in early childhood: A longitudinal analysis

Previous research investigating the correlation between prenatal exposure to per- and polyfluoroalkyl substances (PFAS) and subsequent blood pressure (BP) in offspring has yielded limited and contradictory findings. This study was conducted to investigate the potential relationship between maternal PFAS levels during pregnancy and subsequent BP in early childhood. A total of 129 expectant mothers from the Shanghai Birth Cohort were included in the study. Using high-performance liquid chromatography/tandem mass spectrometry, we measured ten PFAS compounds in maternal plasma throughout the pregnancy. When the children reached the age of 4, we examined their systolic BP (SBP) and diastolic BP (DBP), along with mean arterial pressure (MAP) and pulse pressure (PP). Data interpretation employed multiple linear and logistic regression models, complemented by Bayesian kernel machine regression (BKMR).We found that the majority of PFAS concentrations remained stable during pregnancy. The linear and BKMR models indicated a positive relationship between the PFAS mixture in maternal plasma and offspring's DBP and MAP, with perfluorohexanesulphonic acid (PFHxS) having the most significant influence (PFHxS and DBP [first trimester:β=3.03, 95%CI: (1.01,5.05); second trimester: β=2.35, 95%CI: (0.94,3.75); third trimester: β=2.57, 95%CI:(0.80,4.34)]; MAP [first trimester:β=2.55, 95%CI: (0.64,4.45); second trimester: β=2.28, 95%CI: (0.95,3.61); third trimester: β=2.35, 95%CI:(0.68,4.01)]). Logistic regression highlighted an increased risk of prehypertension and hypertension in offspring with higher maternal PFHxS concentrations during all three trimesters [first trimester: OR=2.53, 95%CI:(1.11,5.79), second trimester: OR=2.05, 95%CI:(1.11,3.78), third trimester: OR=3.08, 95%CI:(1.40,6.79)]. A positive correlation was identified between the half-lives of PFAS and the odds ratio (OR) of prehypertension and hypertension in childhood (β=0.139, P=0.010). In conclusion, this research found maternal plasma PFAS concentrations to be positively associated with BP in offspring, with PFHxS showing the most significant influence. This correlation remained consistent throughout pregnancy, and this effect was proportional to the half-lives of PFAS.

Changes in Concentrations of Polyfluoroalkyl Substances in Human Milk Over Lactation Time and Effects of Maternal Exposure via Analysis of Matched Samples

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are potentially related to many adverse health outcomes and could be transferred from maternal blood to human milk, which is an important exposure source for infants during a long-term period. In this study, the maternal blood of 76 women after delivery and their matched human milk samples obtained at 0.5, 1, and 3 months were analyzed by solid-phase extraction method with metal-organic framework/polymer hybrid nanofibers as the sorbents and ultrahigh-performance liquid chromatography-negative electrospray ionization mass spectrometric for quantitative analysis of 31 PFAS. The perfluorooctanoic acid, perfluorooctane sulfonate, and N-methyl perfluorooctane sulfonamido acetic acid (N-MeFOSAA) contributed to more than approximately 50% of the total PFAS concentrations in blood and human milk, while N-MeFOSAA (median: 0.274 ng/mL) was the highest PFAS in human milk at 3 months. The transfer efficiencies for PFAS from maternal blood to human milk at 0.5 months were generally lower, with medians ranging from 0.20% to 16.9%. The number of PFAS species detected in human milk increased as the lactation time went on from 0.5 to 3 months, and the concentrations of 10 PFAS displayed an increasing trend as the prolongation of lactation time (p < 0.05).

[Determination of seven perfluoroalkyl and polyfluoroalkyl substances in serum of pregnant women and evaluation of neonatal neurobehavior based on high performance liquid chromatography-tandem mass spectrometry]

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) have been extensively used as synthetic fluorine-containing compounds in various consumer products, including surfactants, cookware, lubricants, clothing, and food packaging, since the 1950s. Evidence has shown that PFASs cross the placental barrier and interfere with fetal thyroid hormone homeostasis, which is crucial for fetal growth and neurobehavioral development in children aged 2-9 years. However, no epidemiological data on the association between prenatal PFAS exposure and neonatal neurobehavioral development are available. In this study, we explored the association between prenatal PFAS exposure and neonatal neurobehavioral development based on the Ezhou cohort study. Blood samples (10 mL) were collected during the third trimester of pregnancy (28-36 weeks) at the Ezhou maternal and child health hospital. The blood specimens were centrifuged at 4000 r/min for 15 min immediately after collection, separated, stored at -80 ℃. The samples were analyzed for seven PFASs, namely, perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroheptanesulfonic acid (PFHpS), and perfluorooctane sulfonamide (PFOSA). The PFASs were separated using a C18 column (100 mm×2.1 mm, 1.7 μm) at an oven temperature of 40 ℃, injection volume of 10 μL, and flow rate of 0.4 mL/min via gradient elution with methanol and ammonium acetate aqueous solution. The instrument was operated in negative electrospray ionization mode with multiple reaction monitoring. The correlation coefficients (r2), limits of detection (LODs) and quantification (LOQs), and spiked recoveries of the seven PFASs were 0.993-0.999, 0.006-0.020 ng/mL, 0.020-0.066 ng/mL, and 84.6%-116.8%, respectively. Neonatal behavioral neurological assessment (NBNA) was used to evaluate newborn cognitive development 72 h after birth; this tool consisted of five clusters, including behavior (six items), passive muscle tone (four items), active muscle tone (four items), primitive reflexes (three items), and general assessment (three items). Each item was rated on a three-point scale (0, 1, or 2), with the 20 items having a maximum score of 40. A total of 379 mother-newborn pairs were included in the analysis. The PFASs with the highest exposure levels was PFOA, with median levels of 19.4 ng/mL. Linear regression models were used to test the effects of ln-converted PFAS levels in newborns. After adjusting for confounding factors, the linear regression model showed that PFOS exposure during pregnancy was associated with decreased active muscle tone(β(95% CI): 0.36(-0.64, 0.08)) and general assessment(β(95% CI): 0.34(-0.61, 0.07)) in all newborns. Furthermore, PFNA exposure was associated with decreased passive muscle tone(β(95% CI): 0.38(-0.74, 0.01)) and total NBNA(β(95% CI): 0.37(-0.68, 0.06)). PFDA exposure was associated with decreased behavior(β(95% CI): 0.28(-0.54, 0.01)), while PFHxS exposure was associated with elevated total NBNA(β(95% CI): 0.27(0.05-0.48)). Gender stratification analysis showed that PFOS exposure during pregnancy was associated with decreased active muscle tone(β(95% CI): 0.54(-0.73, 0.35)) and general assessment(β(95% CI): 0.50(-0.88, 0.13)), PFNA exposure during pregnancy was associated with decreased passive muscle tone(β(95% CI): 0.67(-1.2, 0.14)) and total NBNA(β(95% CI): 0.45(-0.91, 0.01)), PFDA exposure during pregnancy was associated with decreased behavior(β(95% CI): 0.44(-0.71, 0.17)), PFHxS exposure was associated with elevated total NBNA(β(95% CI): 0.41(0.02-0.80)) in male newborns, and PFOA exposure was associated with decreased general assessment(β(95% CI): -0.27(-0.51, 0.02)), and PFDA exposure was associated with elevated behavior(β(95% CI): 0.46(0.40-0.52)) in female newborns. The proposed method separates and detects various PFASs without the need for cumbersome pretreatment processes, and has the advantages of low LODs, satisfactory recoveries, and accurate precision. Thus, it allows for the simultaneous analysis of trace PFASs in microserum samples from pregnant women. Our results also showed that prenatal PFAS exposure can lead to neurobehavioral disorders in offspring, with male newborns showing greater sensitivity than female newborns.

Per- and polyfluoroalkyl substances (PFAS) in grocery store foods: method optimization, occurrence, and exposure assessment

Dietary exposure to per- and polyfluoroalkyl substances (PFAS) is poorly understood. Evaluating PFAS in food is complicated by the need to evaluate varied matrices and a lack of a standard, matrix-specific sample extraction methods. Prior food studies implemented universal rather than matrix-specific extraction approaches, which may yield false negatives and an underestimation of PFAS dietary exposure if methods are not suitable to all matrices. Here the objectives were to screen and optimize PFAS extraction methods for plants, tissues, and dairy; apply optimized extraction methods to a grocery store food survey; and compare estimated exposure to published reference doses (RfDs). Optimized, matrix-specific extractions generally yielded internal standard recoveries of 50-150% and matrix spike recoveries of 70-130%. The frequency of PFAS detection in grocery store foods (16 of 22 products) was higher than in previous work. PFAS were detected at concentrations of 10 ng kgdw-1 (perfluorobutane sulfonate; washed green beans and perfluorohexanoic acid; unwashed tomato) to 2680 ng kgdw-1 (perfluorohexane sulfonate; radish). Concentrations of perfluorooctanoic acid (PFOA) in carrots, lettuce, radish, and canned green beans yielded median exposure intake (EI) values of 0.016-0.240 ng per kgbw-day, which exceeded the EPA RfD (0.0015 ng per kgbw-day). Washing reduced radish PFOA concentrations below detection, but EIs at the reporting limit still exceeded the RfD. The combination of improved data quality and greater frequency of PFAS detection vs. prior studies plus EI > RfD for some PFAS suggests a need for matrix-specific extractions and analysis of PFAS in additional grocery store foods from broader geographic regions.

Early-Life Exposure to Perfluoroalkyl Substances (PFAS) and Child Language and Communication Development: A Systematic Review

Language development starts during the fetal period when the brain is sensitive to endocrine disruptions from environmental contaminants. This systematic review aims to systematically summarize the existing literature on early-life exposure to PFAS and children's language and communication development, which is an indicator of neurocognitive development. A structured literature search was conducted using three databases, PubMed, Scopus, and CINAHL, last updated in April 2023. The population was defined as children and young adults. PFAS exposure was assessed pre- or postnatally. The outcome was defined as a language and communication ability assessed with validated instruments, parental self-reports, or clinical language disorder diagnoses. In total, 15 studies were identified for subsequent analyses. Thirteen were performed in background-exposed populations and two in highly exposed populations. There were some indications of potential adverse effects; however, these were not consistent across child sex, age of assessment, or PFAS exposure levels. No systematic effect of early-life PFAS exposure on language and communication development was found. These inconclusive findings may partly be explained by the use of general test instruments with limited validity as to children's language and communication development. Further studies over a wider exposure range using specific language test instruments are needed.

Levels of per- and polyfluoroalkyl substances (PFAS) in Norwegian children stratified by age and sex - Data from the Bergen Growth Study 2

BACKGROUND AND AIM

Due to the persistence, bioaccumulation and potential adverse health effects, there have been restrictions and phase out in the production of certain per- and polyfluoroalkyl substances (PFAS) since the early 2000s. Published serum levels of PFAS during childhood are variable and may reflect the impact of age, sex, sampling year and exposure history. Surveying the concentrations of PFAS in children is vital to provide information regarding exposure during this critical time of development. The aim of the current study was therefore to evaluate serum concentrations of PFAS in Norwegian schoolchildren according to age and sex.

MATERIAL AND METHODS

Serum samples from 1094 children (645 girls and 449 boys) aged 6-16 years, attending schools in Bergen, Norway, were analyzed for 19 PFAS. The samples were collected in 2016 as part of the Bergen Growth Study 2. Statistical analyses included Student t-test, one-way ANOVA and Spearman's correlation analysis of log-transformed data.

RESULTS

Of the 19 PFAS examined, 11 were detected in the serum samples. Perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexanesulfonic acid (PFHxS) and perfluorononaoic acid (PFNA) were present in all samples with geometric means of 2.67, 1.35, 0.47 and 0.68 ng/mL, respectively. In total, 203 children (19%) had PFAS levels above the safety limits set by the German Human Biomonitoring Commission. Significantly higher serum concentrations were found in boys compared to girls for PFOS, PFNA, PFHxS and perfluoroheptanesulfonic acid (PFHpS). Furthermore, serum concentrations of PFOS, PFOA, PFHxS and PFHpS were significantly higher in children under the age of 12 years than in older children.

CONCLUSIONS

PFAS exposure was widespread in the sample population of Norwegian children analyzed in this study. Approximately one out of five children had PFAS levels above safety limits, indicating a potential risk of negative health effects. The majority of the analyzed PFAS showed higher levels in boys than in girls and decreased serum concentrations with age, which may be explained by changes related to growth and maturation.

Prenatal exposure to per- and polyfluoroalkyl substances and pregnancy outcome in Austria

Per- and polyfluoroalkyl substances (PFAS) are a large group of persistent industrial chemicals that can harm reproductive health. PFAS levels were analysed to determine the current sources of exposure and possible associations between prenatal PFAS exposure and adverse pregnancy outcome. Samples from 136 mother-newborn pairs recruited between 2017 and 2019 were analysed for the presence of 31 target PFAS in maternal serum, umbilical cord serum, and placental tissue by high-performance liquid chromatography coupled to a tandem mass spectrometer. Questionnaires and medical records were used to survey sources of exposure and pregnancy outcome, including small for gestational age (SGA), fetal growth restriction (FGR), preeclampsia (PE), preterm birth, large for gestational age (LGA) and gestational diabetes mellitus (GDM). Data were analysed for individual PFAS and sum4PFAS (sum of perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS) serum levels) in logistic regression analyses and categorical regression analyses. Compared to data from a previous Viennese study in 2010-12, sum4PFAS levels were generally lower. Sum4PFAS serum levels of three women (2.2%) exceeded 6.9 µg/L, a level that corresponds to the recently established tolerable weekly intake (TWI) of EFSA for nursing mothers aged 35 years; in the 2010/2012 study it was 13.6%. The large contribution of unidentified extractable organofluorine (EOF) fractions to total PFAS exposure is a concern. Study site, mean maternal corpuscular hemoglobin (MCH), use of facial lotion, and owning upholstered furniture were significantly influencing maternal exposure. While no effect of sum4PFAS on pregnancy outcome could be detected, we found highest placental PFDA levels in SGA births. PFHxS levels in umbilical cord and placenta were highest in preterm births. Further studies are needed to elucidate the relationship of prenatal PFAS exposure and pregnancy outcome, in particular to confirm whether and how placental PFDA levels may contribute to an increased risk for SGA.